Splash Net Express Arctic Armor Rugged Mesh Winter Cover for 18ft Round Above Ground Pools Rugged Mesh Winter Cover for 18ft Round Above Ground Pools / Cover Size: 22ft Tightly woven scrim holds together to ensure no gaps or holes Allows through only rain water and very fine silt Allows rain and snow to slowly fill your pool saving water and chemicals in the spring U.V. protected woven polyethylene- Allows almost no Sunlight Through